TABLE 5.

Univariate and multivariate analyses of selected outcomes

	Univariate		Multivariate
Variable	HR (95% CI)	p Value	HR (95% CI)	p Value
Local failure
Treatment group
No ipilimumab	Ref	Ref	Ref	Ref
Concurrent ipilimumab	0.342 (0.123–0.828)	0.02	0.360 (0.129–0.873)	0.02
Nonconcurrent ipilimumab	0.846 (0.471–1.569)	0.59	0.861 (0.478–1.600)	0.63
Ipilimumab dose
3 mg/kg	Ref	Ref	—	—
10 mg/kg	1.795 (0.793–3.703)	0.15	—	—
Tumor vol
<1 cm3	Ref	Ref	Ref	Ref
>1 cm3	2.098 (1.077–3.826)	0.03	2.020 (1.034–3.695)	0.04
Edema vol
<2.5 cm3	Ref	Ref	—	—
>2.5 cm3	1.401 (0.733–2.525)	0.29	—	—
Edema index
<10	Ref	Ref	—	—
>10	0.855 (0.208–2.330)	0.79	—	—
Lesion location
Cerebral hemispheres	1.015 (0.444–2.926)	0.98	—	—
Other	Ref	Ref	—	—
SRS dose, Gy	1.11 (0.872–1.455)	0.42	—	—
Tumor response at 1.5 mos	0.234 (0.114–0.457)	<0.001	0.498 (0.220–1.082)	0.08*
Edema response at 1.5 mos	0.300 (0.145–0.584)	<0.001	0.522 (0.242–1.076)	0.08*
Tumor response at 3 mos	0.086 (0.034–0.193)	<0.001	0.131 (0.047–0.335)	<0.001*
Edema response at 3 mos	0.088 (0.032–0.204)	<0.001	0.125 (0.044–0.309)	<0.001*
Any lesion hemorrhage
Treatment group
No ipilimumab	0.570 (0.274–1.150)	0.12	0.469 (0.212–1.013)	0.05
Concurrent ipilimumab	Ref	Ref	Ref	Ref
Nonconcurrent ipilimumab	0.480 (0.264–0.888)	0.02	0.395 (0.208–0.763)	0.006
Ipilimumab dose
3 mg/kg	Ref	Ref	—	—
10 mg/kg	0.917 (0.345–2.046)	0.85	—	—
Tumor vol
<1 cm3	Ref	Ref	—	—
>1 cm3	1.528 (0.727–2.906)	0.25	—	—
Edema vol
<2.5 cm3	Ref	Ref	—	—
>2.5 cm3	0.849 (0.404–1.611)	0.63	—	—
Edema index
<10	Ref	Ref	—	—
>10	1.388 (0.482–3.158)	0.50	—	—
Lesion location
Cerebral hemispheres	6.868 (1.512–121.405)	0.007	6.307 (1.376–111.784)	0.01
Other	Ref	Ref	Ref	Ref
SRS dose, Gy	1.095 (0.876–1.423)	0.45	—	—
Tumor response at 1.5 mos	0.558 (0.318–0.985)	0.04	1.063 (0.550–2.076)	0.86
Edema response at 1.5 mos	0.635 (0.362–1.118)	0.11	1.093 (0.577–2.089)	0.79
Any lesion hemorrhage
Tumor response at 3 mos	0.292 (0.158–0.544)	<0.001	0.225 (0.107–0.476)	<0.001
Edema response at 3 mos	0.301 (0.162–0.555)	<0.001	0.262 (0.130–0.523)	<0.001
Any TRICs
Treatment group
No ipilimumab	Ref	Ref	—	—
Concurrent ipilimumab	1.283 (0.457–3.681)	0.63	—	—
Nonconcurrent ipilimumab	1.145 (0.490–2.980)	0.76	—	—
Ipilimumab dose
3 mg/kg	Ref	Ref	—	—
10 mg/kg	0.687 (0.162–2.011)	0.53	—	—
Tumor vol
<1 cm3	Ref	Ref	—	—
>1 cm3	1.160 (0.392–2.773)	0.77	—	—
Edema vol
<2.5 cm3	Ref	Ref	—	—
>2.5 cm3	1.065 (0.425–2.335)	0.88	—	—
Edema index
<10	Ref	Ref	—	—
>10	0.418 (0.023–1.947)	0.32	—	—
Lesion location
Cerebral hemispheres	3.767 (0.810–67.015)	0.10	—	—
Other	Ref	Ref	—	—
SRS dose, Gy	0.933 (0.728–1.258)	0.62	—	—
Tumor response at 1.5 mos	0.138 (0.055–0.308)	<0.001	0.144 (0.053–0.359)	<0.001
Edema response at 1.5 mos	0.219 (0.091–0.476)	<0.001	0.297 (0.116–0.703)	0.005
Tumor response at 3 mos	0.298 (0.131–0.675)	0.004	0.867 (0.346–2.120)	0.76
Edema response at 3 mos	0.248 (0.106–0.558)	<0.001	0.443 (0.176–1.066)	0.07

^*Due to collinearity between model terms, these risk factors were analyzed separately.